The present application relates generally to sensors in vehicles, and more particularly, to devices for sensing wear of a vehicle component.
Wear components, such as tire tread and brake pads, are abraded by wearing surfaces, such as pavement and brake rotors. At some point, wear components are so worn that their continued use may be dangerous. Presently, government regulations require vehicle owners, particularly commercial operators of vehicles such as trucks, to inspect wear and remaining life of certain vehicle components, such as brake pads.
It would be particularly useful to be able to monitor brake pad wear during vehicle operation. Then, the operator would simply be notified when replacement is required. One method for on-the-fly brake pad wear detection employs clip-on acoustic devices, which can be noisy and disturbing to the driver and those around the vehicle. Further, the driver may not understand the audible signal produced by such acoustic devices or may ignore it. Other solutions, such as providing inspection openings in calipers (which weaken the caliper) also exist. These solutions, however, have proven to be complex and may also be expensive to implement.
Another solution places an electronic sensor within a vehicle component to monitor its condition. These sensors often require wires and connectors which may preclude their use altogether, and at least makes such installations cumbersome. Wireless sensor design for wear detection has been attempted, using multi-frequency transmitters. Such designs may further require multiple sensors, raising the cost of manufacture. Moreover, the position of the sensor system within the vehicle component can vary during manufacture and may shift during operation, preventing accurate assessment of the vehicle component's condition.
It would be highly desirable to have a relatively simple and cost effective system for vehicle component wear detection that also ensures improved estimation of the wear component's condition.